Cellular Respiration
pp. 77 to 82
What is it?
• A process to convert glucose to ATP in
order to obtain energy
• Occurs in all organisms (plants and
animals)
– Plants continue their quest to get food
(glucose is made in photosynthesis. Cellular
respiration continues the process)
Glucose + Oxygen = Carbon Dioxide + Water + Chemical
Energy
C6H12O6
6O2
6CO2
6H2O
36 ATP
Types of Cellular Respiration
1. Aerobic cellular respiration
•
•
•
Uses oxygen in process
Makes large # of ATP molecules
Primary process for humans
2. Anaerobic cellular respiration
•
•
No oxygen is used
Makes small # of ATP molecules
Aerobic Respiration
1. Glycolysis (in cytoplasm)
•
A molecule of glucose (C6H12O6) is broken two
into 2 molecules of pyruvate (C3H6O3).
Energy is released (2 ATP)
2. Oxidative Respiration (in mitochondria)
•
The 2 pyruvates react with 6 molecules of O2
(that is inhaled) to make 6 molecules of CO2
and 6 molecules of water. Energy is released
(34 ATP).
Oxidative respiration
36 ATP total!
Anaerobic Respiration
•
No oxygen, but ATP still can be made
from glucose in a special way! Occurs in
cytoplasm of cell.
1. Ethanol Fermentation (bread, liquor,
soy sauce, etc)
2. Lactic Acid Fermentation (heavy
exercise)
Ethanol Fermentation
1. Glycolysis - Glucose broken down into 2
pyruvate. Energy is released (2 ATP).
2. Enzyme converts the 2 pyruvates to CO2
and ethanol.
•
•
Baking bread  yeast eats the glucose
in flour and expels CO2 and ethanol
(sweet smell). Ethanol evaporates when
baked.
Alcohol  yeast eats glucose in sugary
grape juice and expels CO2 and ethanol.
Lactic Acid Fermentation
• When working out, humans convert glucose into
ATP to get energy to sustain workout.
• Glucose broken down into 2 pyruvates. Energy is
released (2 ATP).
• Eventually, oxygen cannot keep up with demands
of glucose conversion (there is just not enough
oxygen for this amount of energy needed)
• Enzyme in muscle cells convert the 2 pyruvates
into lactic acid
• The more lactic acid, the more sore/stiff your
muscles are.
Aerobic vs. Anaerobic
• With oxygen
• Occurs in
mitochondria of cell
• 36 ATP molecules
made
• More efficient
• Plants, animals use
this
• No oxygen
• Occurs in cytoplasm
of cell
• 2 ATP molecules
made
• Less efficient
• Simple organisms
(yeast, bacteria, etc)
use this; humans
doing heavy exercise
Unit Test – Oct. 2nd
• Multiple Choice (8 questions)
• Short Answer
– Labelling (4 parts to label & their functions)
– Choose 3 out of 4 pair of terms to compare &
contrast
– 1 very short answer pertaining to passive
transport
• Longer Answer
– Choose 2 out of 3 questions to answer
– Emphasis is on cellular processes! (eg. How
certain things work – lock and key, a type of
respiration, etc)